Conditioning shampoos comprising various combinations of detersive surfactant and hair conditioning agents are known. These shampoos have become more popular among consumers as a means of conveniently obtaining hair conditioning and hair cleansing performance all from a single hair care product.
Especially popular among consumers are those conditioning shampoos which comprise a cationic hair conditioning polymer. The cationic polymer provides the shampoo with wet hair conditioning, and in particular helps prevent tangling of hair during and after rinsing, and ideally also should provide the wet hair with a smooth, silky texture that consumers can associate with optimal conditioning and cleaning performance. For many of these cationic polymers, however, the wet hair feel during and after rinsing is characterized by consumers as an undesirable, slimy feel rather than a more desirable, smooth, silky texture. Although consumers continue to use such products for the cleaning and conditioning benefits, they often excessively rinse their hair of the conditioning shampoo in attempts at washing away the slimy, wet hair feel of the cationic conditioning polymer.
One attempt at improving the overall conditioning performance from a conditioning shampoo involves the use of silicone conditioning agents. These conditioners provide improved hair conditioning performance, and in particular improve the softness, and clean feel of dry conditioned hair. These silicone conditioners, however, provide less than optimal wet hair conditioning. As such, cationic conditioning polymers are often combined with the silicone conditioners in a shampoo to improve wet hair conditioning. Although wet hair conditioning is then improved by such a combination, e.g., detangling, smoother wet hair texture, the improvement is often accompanied by the development of the slimy, excessively conditioned wet hair feel from the added catonic conditioning polymer.
Yet another attempt at improving the overall conditioning performance from a conditioning shampoo involves the use of organic conditioning oils, examples of which include hydrocarbon oils, higher alcohols, fatty acid esters, glycerides, fatty acids and various combinations thereof. These conditioning oils provide the hair with luster, shine and a soft hair feel when dried. Although these conditioning oils can also provide some wet hair conditioning benefits, the wet conditioned hair is often characterized as slimy or excessively conditioned, especially when the conditioning oil is used in combination with a cationic conditioning polymer.
It has now been found that select synthetic esters, when used in combination with a cationic hair conditioning polymer and anionic detersive surfactant component, provide improved conditioning performance, and in particular provide improved wet hair conditioning in the form of improved wet hair feel. The select synthetic esters help to minimize or eliminate the slimy, excessively conditioned wet hair feel associated with cationic conditioning polymers, without unduly impairing wet hair conditioning.
To realize these conditioning benefits, it has been found that the synthetic esters must contain from 2 to 4 esterified C8 to C10 groups, and be water-insoluble, and have a viscosity of from about 1 to about 300 centipoise as measured at 40.degree. C. The synthetic ester content must also represent from about 2.5% to about 100%, by weight of the total liquid fatty ester content of the shampoo composition. It is believed that all or most of the synthetic ester is solubilized into the surfactant micelles of the shampoo composition. It is also believed that this solubilization into the micelle, rather than mere dispersion outside the micelle as water insoluble, oil droplets, is a key factor in providing the improved conditioning performance of the shampoo compositions herein.
It is therefore an object of the present invention to provide a hair conditioning shampoo composition with improved hair conditioning performance, and further to provide such a composition with improved hair conditioning performance which also contains a cationic polymer conditioning agent. It is a further object of the present invention to provide such compositions that provides improved wet hair conditioning, and in particular minimizes or eliminates the excessively conditioned, slimy wet hair feel associated with the use of a cationic hair conditioning polymer.